Biohydrogen Production from Biomass and Wastes via Dark Fermentation: A Review

The present review article aims to summarize the microbiological and technological background of the dark fermentation processes for hydrogen generation, emphasising on the exploitation of biomass and wastes as potential feedstocks. The basic principles, the microbiology and the current technology of the processes are outlined. Subsequently, the use of different types of biomass and wastes that have so far been tested as feedstocks is analysed focusing on the advantages, possible limitations and future prospects of their exploitation. Moreover, different types of so far suggested pretreatment methods for better utilisation of the feedstocks are presented, pointing out the advantages and disadvantages of each method. Finally, methods for possible further utilisation of the generated by-products are laid out as well as the present status of the real scale applications.